| 释义 |
Earthquakes produce two types of seismic waves.地震产生两种地震波。The frequent occurrence of earthquakes in the area means that the buildings must be specially designed to withstand the force.这一地区频繁发生的地震意味着建筑物必须经过特别设计，以抵抗地震波的冲力。An earthquake shook a wide area of southern Italy on Saturday.星期六一场地震波及了意大利南部广大地区。 |